Pressing machine



July 9, 1940.

O. H. PEARSON El AL PRESSING MACHINE Filed Aug. 27, 1937 2 Sheets-Sheet 1 0 I P IN\-ENTOR$. and -E. Pearson y 1940- o. H. PEARSON ET AL PRESS ING MACHINE Filed Aug. 27, 1937 2 Sheets-Sheet 2 INVENTORS, O. H. Pearson nd E. son BY 5 ATTORNEY.

Pear 3 Patented July 9, 1940 PRESSIN G MACHINE Otto H. Pearson and Edward Pearson, Salt Lake City, Utah, asslgnors,

by mesne assignments, to

Nicholas L. Strike, Salt Lake City, Utah Application August "27,

16 Claims.

Our invention relates to pressing machines, and more particularly to two-hand control pressing machines.

An important object of the invention is the provision in pneumatic means for operating such a machine, of a pilot valve, operable by relatively slight manual power, to actuate said pneumatic means.

In a machine of the character mentioned having three-position manuals for actuating the pilot valve, an object of the present invention is the elimination of spring means that moves the manuals from an intermediate to an inoperative position.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description.

In the drawings, like reference characters designate similar parts in the several views.

Figure lis a side elevation of an embodiment of our invention.

Figure 2 is an enlarged section, taken on the line 2-2 of Figure 1.

Figure 3 is a reduced elevation, looking in the direction of the arrows 3-3 of Figure 2.

Figure 4 is an elevation, partly in section, taken on the line 33 of Figure 2.

Figure 5 is a reduced plan view, similar to Figure 2, but showing another position in the operation.

Figure 6 is an enlargement of a detail hereinafter more fully described.

Figure 7 is a broken, enlarged section of pneumatic driving means comprised in the embodiment.

Figure 8 is a section through valve means for controlling the mechanism of the machine.

Referring more in detail to the drawings, the reference number Ill generally designates the frame of the present machine, which supports a relatively stationary buck l2 and a pivotally mounted head I3. An arm I3, which supports the head I3, is pivotally mounted on the frame at I5. The arm M is in turn pivotally connected with a link I6.

The link I6, together with a therewith pivotally connected link I1, form a toggle generally designated I8. The lower end of the link IT has a pivotal connection with a piston rod IS. A roller bearing 20, on theknuckle formed by the links I! and piston rod I9, rides on a cam 2| having an upwardly inclined face 22 and a concave top face 23. A spring 6| may be coiled about the piston rod I9, to cushion inward move- 1937, Serial No. 161,188 (C 192-131) ment of'the rod I9 into its cylinder hereinafter described.

One end of an oscillating tie bar 25 is pivotally mounted on a spindle 26 on the frame. The other end is connected with an ofiset stub shaft 26 at the elbow of the toggle I8.

A cylinder 21 has a ball and socket connection 28 with the frame of the machine, to permit oscillation of the cylinder. A piston 29 in the cylinder is mounted on the piston rod I9.

Heavy coil springs 30 and 3| tend to move the head I3 to the open position shown in Figure 1. The link l5 carries an ear 32 for reciprocating movement of a rod 33. A stop 34 on the rod 33 provides an abutment opposed to the ear 32, between which a spring 35, coiled about the rod 33, is disposed. An auxiliary spring 36, connecting with the frame and with the stop 38, may also be used. The springs 35 and 35 tend to move the rod toward the front of the machine.

Another stop 3'! is disposed on the rod 33 on the other side of the ear 32 from the stop 33. The stop 31 may be the form of a nut on a threaded portion of the rod 33, to permit adjustments of the stop 31. By this arrangement, movement of the ear 32 in one direction compresses the spring 35, tending to move the rod 33 forward, and movement of the ear 32 in the opposite direction causes it to strike the stop 3?, efiecting rearward movement of the rod.

A pipe 38 supplies air pressure, or other pressure fluid, to the machine. A manual valve 39 controls the flow therethrough. A branch 40 of the pipe 38 leads to a valve casing 4|, hereinafter more fully described. The pipe 38 connects with a valve housing 42.

The housing has chambers 33 and M connecting by means of a passage 45. A ball valve 46 in one position closes the passage 35. A coiled spring M tends to move the ball valve 66 to said passage closing position. To aid in assembling, the chamber 63 is closed by a screw plug 48. A pipe 49 connects the chamber 63 with a passage 50 in head 5i of the cylinder 21. The passage 50 directs pressure fluid into the cylinder against the face of the piston 29, to urge the piston to the right in Figure 7.

An exhaust 52 connects with a chamber 53 in the valve housing 42. The chambers 64 and 53 connect by means of a passage 53, the walls of which passage provide a valve seat.

A valve 55, having a relatively slender pin 55 integral therewith, is disposed to reciprocate in the housing 62. The valve 55 when depressed engages the seat in the passage 54. When so depressed, the pin 58 pushes the ball valve 48 from its passage closing position, against the action of the coiled spring 41. Thus in said depressed position, the valve 55 closes the passage 54 and opens the passage 46, permitting fluid pressure to flow from the pipe 88, through the chamber 43, through the passage 46 through the chamber 44, and through the pipe 49 to the cylinder 21, to actuate the piston 29.

When the valve is released from said depressed position, the coiled spring 41 seats the ball valve 46 and through the intermediary of the pin 56 causes the valve 55 to move from its seat. In this position of the two valves, the flow of pressure fluid from the source to the cylinder is stopped, but since the chambers 44 and 52 are now connected, pressure fluid ahead of the piston 29 may pass through chamber 44, through passage 54, through chamber 58-and out at the exhaust 62.

A shell 51 has bolted between the complementary halves thereof, a diaphragm 58. A pin 59 fastened to the diaphragm reclprocates therewith. At the opposite side of the diaphragm from the pin 59, the shell 51 receives pressure fluid from a pipe 69. It will be noted that the pin 59 is arranged to depress or actuate the valves 55 and 46 against the action of the spring 41.

The mechanism is actuated by a pair of spaced manuals 62 and 63. It is to be understood that the manuals are so spaced that they cannot be operated by a single hand, but require both hands of the operator to operate. This arrangement prevents the operator from getting his or her hands caught between the descending head i8 and the buck l2, which would injure and burn the operators hands.

A table 64 is shown under the buck, and a flange 65 depends from the table. Openings 68 and 61 are arranged in the flange 86 to reach the ends only of the manuals 62 and 62 respectively.

The manuals 62 and 68 are pivoted at 68 and 69, which pivots are mounted upon a platform beneath the table 64. A strap 1| ties the pivots 68 and 69 together. Mounted rigidly on the manuals 62 and 88 and forming bell cranks therewith are arms 12 and 18 respectively. Stops 14 and. limit outward movement of the arms 12 and 13. The bolts I88 rigidly fasten the arms 12, 13 to the manuals 62, 68 respectively. The bolts Hill are not pivots.

A whippletree 15 is fastened at its ends to the arms 12 and 18, by means of links 16 and 11 respectively. The whippletree, adjacent its midpoint, carries a head 18 which is pivotally connected to the whippletree. The head 18 has a cylindrical recess for a relatively stifi spring 19.

A finger 88 has a head 8| in the recess of the head member 18. The head member 18 itself limits the outward movement of the finger head 8| and the inward movement of the flnger is limited by the spring 19.

A valve 82 is mounted for reciprocation in the valve casing 4|. A nut 84 on the valve 82 limits inward movement of said valve relative to the casing 4|. The nose of the valve 82 is elongated, as shown at 85, and engages a ball valve 86. A coiled spring 81 behind the ball valve 86 urges same against its seat in the casing 4|. When the valve 82 is moved inward relative to the easing 4|, the ball valve 86 is moved from its seat against the action of the spring 81.

The valve casing 4| has a chamber 88 that is provided with exhausts 89. The pipe 68 connects with a chamber 98 in the casing 4|. The

pipe 48 connects with a chamber 8| also in the casing 4|. A pipe 92 is normally closed but may be connected with valve control means (not shown) if the machine is connected in tandem with another machine.

The nose 85 of the valve 82 fits loosely in the casing, whereby fiuid pressure may pass around same at all times. The chambers 88 and 88 and chambers 98 and 9| are connected by the passages in which the nose 86 lowely fits. A screw plug 98 closes the end of the casing 4| adjacent the spring 81.

When the spring 81 is seating the ball valve 86 upon its seat (which is its normal position when the manuals are in the full line positions shown in Figure 2), the flow of pressure fluid from the source is stopped. Moreover, in this position the exhausts 89 are connected with the diaphragm shell 51, whereby the diaphragm may be moved by its spring 94 to the position shown in Figure 8, releasing the valve 66.

When the valve 82 is moved inward relative to the casing 4|, the taper oi the valve 82 seats and thus seals the passage between the chambers 88 and 98, thereby shutting oil. the exhausts. At the same time the ball valve 86 is unseated, connecting the chambers 99 and 9| and thereby permitting fluid pressure to fiow from the pipe 40 to the pipe 68,thus actuating the diaphragm 58, which in turn operates the main supply valve 46. It will thus be seen that the valve 86 acts as a pilot valve, requiring only relatively slight pressure to operate the main valve 48 or the machine.

To temporarily limit movement of the arms 12 and 13 toward each other, a barrier 96 is provided. It is in the shape of a bell crank 96 pivoted at 91. The rod 88 connects with the lower end of the bell crank 96, to move the barrier 95 to and from a position between the arms 12 and 18. The barrier is beveled, to force the arms 12 and 18 apart (from the position shown in Figure 5) when the barrier is moved between them. The arms 12 and 18 have a limited movement between the stops 14 and 16 and the barrier. A stop 99 limits inward movement of the arms 12, 13, when the barrier is removed.

To initiate the operation of the present invention, both manuals 62, 68 and must be moved from the full line to the broken line positions shown in Figure 2. If only one manual is so moved, the whippletree 15 is turned upon the head 18 without moving said head..

When both manuals are moved to the broken line positions, the head 18 is advanced to the right in Figure 2. This movement causes the tinger 88 to actuate the valve 82, which opens the pilot valve 86 in the manner described hereinbefore. The pressure fluid then actuates the diaphragm, which opens the main valve 46 as explained hereinbefore. Fluid pressure is thereby admitted to the cylinder 21, thus driving the piston 29;

The force against the piston moves the roller bearing 28 up the inclined face 22 and then around the concave face 23. This movement causes the closing of the head I8 down upon the buck l2, as shown in broken lines in Figure 1, against the action of the springs 88, 3|.

During the foregoing operation, the arms 12, 13 are against the sides of the barrier 95. If, prior to the time the head l3 engages or substantially engages the buck i2, the operator releases either hand, the whippletree is turned, or if both hands are released, the force upon the whippletree is being too little released. In either event, there is nothing to maintain the pilot valve 86 off its'seat. When said valve is seated, the flow of fluid pressure is checked, releasing the main valve 46 and permitting same to be seated, which checks the pressure flow to the cylinder 21. Since the cylinder is then connected with the exhaust 52, the large coil springs 30, 3| may and do return the head to the open, full line position shown in Figure 1.

By the time the head l3 engages or substantially engages the buck I2, the ear 32 has engaged the nut 31, thus drawing the rod 33, which withdraws the barrier from between the arms 12, 13. The operator may then move the manuals to the locked position shown in Figure 5. The locked position is the over-center or past center position of the arms 12,13 and the links 16, 11,

which arms and links respectively form opposed toggles. In this position, the operator may release both manuals and the head l3 will remain in pressing engagement with the buck I2.

To raise the head I3, all that is necessary is to release either manual or both manuals. The manuals float in the inoperative or rest position designated by the full lines in Figure 1. This machine is marked by the absence of spring means to maintain the manuals in the full operative position (Figure 5), and by the absence of spring means that move the manuals from the intermediate (broken line position in Figure 1) to the inoperative position. The springs 19 and 87 are only to compensate for Wear of the valves 82 and 86 and their respective seats and are not adapted nor intended to perform the functions mentioned earlier in this paragraph, there stretch or extent in such springs. Moreover, these springs are strong springs and are compressed to a relatively slight extent in the operation of the machine.

Upon release of either manual or both man uals, the fluid pressure is cut oil, the pressure in the cylinder is exhausted, allowing the springs 38, 3i to raise the pressing head I3. At the same time the ear 32 moves away from the stop 31, thus releasing the rod 33 and allowing the springs 35, 36 to move the barrier up between the arms 12, 73.

It will be seen that the operation is in two steps: (a) The manuals are movable from the full line, inoperative position of Figure 2 to the broken line, intermediate position of the same figure; and (b) the manuals are movable from said broken line, intermediate position, to the full operative position shown in Figure 5. The first step lowers the head I3 into contact with the buck l2 and the second step locks the manuals with the head in such contacting position.

While we have illustrated and described what we now regard as the preferred embodiment of our invention, the construction is, of course, subject to modifications without departing from the spirit of our invention. We, therefore, do not wish to restrict ourselves to the particular form of construction illustrated and described, but desire to avail ourselves of all modifications which may fall within the scope of the appended claims.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

l. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, means to lock the manuals in full operative positions, means governed b1 the-relative positions of the head and bed members controlling movement of the manuals from intermediate to full operative positions, a source of pressure fluid connected with said operating mechanism, a valve controlling the entire flow of said pressure fluid to said mechanism, means controlling said valve, and mechanism operable by pressure fluid from said source arranged to actuate the last mentioned means when the manuals are in the intermediate or full operative positions.

2. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, means to lock the manuals in full operative positions, means governed by the relative positions of the head and bed members controlling movement of the manuals from intermediate to full operative positions, a source of pressure fluid connected with said operating mechanism, valve means controlling the entire flow of said pressure fluid to said mechanism, fluid actuated means controlling said valve means, conduit means to convey pressure fluid to said fluid actuated means, and valve means controlling the flow through said conduit means and operable by the manuals when same are in the intermediate or full operative positions.

3. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism,,including spaced manuals movable from inoperative tointermediate positions and thereafter to full operative positions, means to lock the manuals in full operative positions, means governed by the relative positions of the head and bed members controlling movement of the manuals from intermediate to full operative positions, a source of pressure fluid connected with said operating mechanism, valve means controlling the entire flow of said pressure fluid to said mechanism, a diaphragm controlling said valve means, conduit means to convey pressure fluid to said diaphragm, and valve means controlling the flow through said conduit means and operable by the manuals when same are in the intermediate or full operative positions.

4. A pressing machine comprising head and bed members, at least one of Which is movable, a fluid motor arranged to operate the movable member, and control means for the fluid motor, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, means to lock the manuals in full operative positions, means governed by the relative positions of the head and bed members controlling movement of the manuals from intermediate to full operative positions, main valve means connected to control the entire motive fluid to the motor, and a pilot valve connected to operate the main valve means, the pilot valve operable by the manuals when same are in the intermediate or full operative positions.

5. A pressing machine comprising head and bed members, at least one of which is movable, a fluid motor arranged to operate the movable member, and control means for the fluid motor, including spaced manuals movable from inoperativeto intermediate positions and thereafter to full operative positions, means to lock the manuals in full Operative positions, means governed by the relative positions of the head and bed members controlling movement of the manuals from intermediate to full operative, positions, a main valve connected to control motive fluid to the motor, and arranged to move with the flow of the motive fluid when moving to a closed position, and a pilot valve arranged to move with the flow of the motive fluid when moving to a closed position, the pilot valve being connected to maintain the main valve in an open position when the manuals are in the intermediate or full operative positions, the pilot valve and main valve being movable to closed positions when the manuals are moved to inoperative positions.

6. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, a Whipple-tree connected to be moved to a position in which said control means is actuated, over-center toggles respectively connecting the manuals with the whippletree, the toggles being at one side of dead center when the manuals are in inoperative or intermediate positions and being locked at the opposite side of dead center when the manuals are in full operative positions, means governed by the relative positions of the head and bed members controlling movement 01' the toggles from the first mentioned. side of dead center to the last mentioned side thereof, and resilient means arranged to give as the toggles pass dead center.

7. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member,

and control means for said mechanism, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, a Whipple-tree connected with the manuals and movable to a position in which said operating mechanism is actuated, when the manuals are moved to intermediate or full operative positions, releasable and resilient means tending to maintain the whippletree in said mechanism actuating position, said means being actuated by movement of the manuals to full operative positions, and being releasable by movement of a manual to an inoperative position, and means governed by the relative positions of the head and bed members controlling movement of the manuals from intermediate to full operative positions.

8. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable from inoperative to operative positions, a whippletree connected with the manuals and movable to a position in which said operating mechanism is actuated, when the manuals are moved to operative positions, and releasable means to maintain the whlppletree in said mechanism actuating position, said means being actuated by movement of the manuals to full operative positions, and being releasable by movement of a manual to an inoperative position and resilient means tending to resist movement of the whippletree from its said actuating position.

9. A pressing machine comprising head and bed members, at least one or which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable Irom inoperative to intermediate positions and thereafter to full operative positions, a source oi! pressure fluid connected with said operating mechanism, a valve controlling the entire flow of said pressure fluid to said mechanism, over-center toggles respectively connected with the manuals and connected with the single valve, the toggles being at one sideof dead center when the manuals are in inoperative or intermediate positions and being locked at the opposite side of dead center when the manuals are in full operative positions, and means governed by the relative positions of the head and bed members controlling movement of the toggles from the first mentioned side of dead center to the last mentioned side thereof.

10. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, a main valve connected to control the entire flow of motive fluid to the motor, a pilot valve connected to operate the main valve, over-center toggles respectively connected with the manuals and with the pilot valve, the toggles being at one side of dead center when the manuals are in inoperative or intermediate positions and being at the opposite side of dead center when the manuals are locked in full operative positions, and means governed by the relative positions of the head and bed members controlling movement of the toggles from the first mentioned side of dead center to the last mentioned side thereof.

11. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism for the movable member, and control means for said mechanism, including spaced manuals movable from inoperative to intermediate positions and thereafter to full operative positions, the manuals having elements moving towards each other in these movements, a movable barrier disposed in the space between said elements, the single barrier being arranged to oppose movement of the elements towards each other, to prevent movement of the manuals from intermediate to full operative positions until the head and bed members are substantially in contact with each other, and means controlled by said operating mechanism thereupon moving the barrier from its said opposing position.

12. A pressing machine according to claim 3, in which the valve controlling the flow of pressure fluid to the press operating mechanism comprises an intake valve and an exhaust valve, means to maintain either the intake or exhaust valve away from its seat while the other valve is seated, and spring means tending to move the diaphragm to an inoperative position with regard to the first mentioned valve.

13. In a pressing machine of the class having spaced manuals controlling the mechanism 01' the machine, wherein the manuals are movable from inoperative to intermediate positions and to full operative position, and wherein means are provided for locking the manuals in full operative position, the combination with said manuals of a valve mechanism comprising an intake valve and an exhaust valve, means to maintain either one or the other of the valves away from its seat while the other valve is seated, and spring means tending to seat the exhaust valve, to take up wear between the exhaust valve and its respective seat.

14. In a pressing machine of the class having spaced manuals controlling the mechanism of the machine, wherein the manuals are movable from inoperative to intermediate positions and to full operative position, and wherein means are provided for locking the manuals in full operative position, the combination with said manuals of a valve housing having connecting chambers, one chamber connecting with a source of motive fluid, the other chamber being connected to supply said motive fluid to operating mechanism of the machine, the housing having an exhaust port, and intake valve controlling the connection between the chambers, an exhaust valve controlling the exhaust port, means to maintain either one or the other of the valves away from its seat while the other valve is seated, and spring means tending to seat the exhaust valve, to take up wear between the exhaust valve and its respective seat.

15. A pressing machine comprising head and bed members, at least one of which is movable, operating mechanism therefor, and control means for said mechanism including spaced manuals movable from an inoperative to an in termediate position and to a full operative position, the manuals being automatically maintained in the full operative position when moved thereto, stop means governed by the relative position of the head and bed members to control the movement of the manuals from intermediate to full operative position, a whippletree connected with the manuals and movable thereby, and valve means connected to be controlled by movement of the whippletree, when the manuals are moved from inoperative to intermediate position and to the full operative position after the stop means has been actuated and resilient means arranged to permit movement of the manuals to the full operated position.

16. A control for presses of the class having a bed member and a head member movable to the bed member, comprising control means for the head member including spaced manuals movable from an inoperative to an intermediate position and to a full operative position, the manuals being automatically maintained in the full operative position when moved thereto, a whippletree connected with the manuals and movable thereby, a resilient connector pivotally mounted on the whippletree, requiring movement of both ends of the whippletree to advance the connector forward, the whippletree being connected at opposite sides of the pivot with the manuals respectively, a valve operable by forward movements of the connector, movement of the manuals from the inoperative to the intermediate position effecting forward movement, of the connector, a stop to prevent further movement of the manuals until the head has moved substantially to the bed, and means to withdraw the stop at that time to allow movement of the manuals to full operative position.

0. H. PEARSON. EDWARD PEARSON. 

